A thin film magnetic head having a particularly short throat height and a fine pole portion with no magnetic saturation and a small magnetic flux leakage is manufactured on a mass scale in an efficient and speedy manner as follows. After forming a lower shield for a magnetoresistive type thin film magnetic head on a substrate, a magnetoresistive layer embedded in a shield gap layer is formed, a first magnetic layer constituting an upper shield for the magnetoresistive type thin film magnetic head as well as a lower pole of an inductive type thin film magnetic head is formed, a recess is formed in its surface, an insulating layer is embedded in the recess, and a surface is flattened. On the thus flattened surface, is formed a write gap layer, and a second magnetic layer constituting a pole chip is formed into a desired pattern. A rear edge of said second magnetic layer is extended inwardly beyond an edge of the recess opposing to an air bearing surface. On the write gap layer, first and second layer thin film coils are formed on the write gap layer such that the thin film coils are supported by photoresist insulating layers, a third magnetic layer is formed such that a front end of the third magnetic layer is retarded from the air bearing surface and the third magnetic layer is coupled with the first magnetic layer at a portion remote from the air bearing surface, and then an overcoat layer is formed on a whole surface. A position of said edge of the recess formed in the first magnetic layer opposed to the air bearing surface is not deviated during the manufacturing process and the air bearing surface is polished while said position is used as a throat height zero reference position.
Legal claims defining the scope of protection, as filed with the USPTO.
1. A thin film magnetic head comprising: a substrate; a first magnetic layer supported by said substrate and having a recess formed in a surface thereof, said surface being opposite to a substantially flat surface on which the first magnetic layer is supported, the first magnetic layer is substantially flat along its entire length; a first insulating layer formed in said recess formed in said surface opposite to the surface on which the first magnetic layer is supported by the substrate, said first insulating layer being coplanar with said surface of the first magnetic layer; a write gap layer formed along the coplanar surfaces of the first magnetic layer and the first insulating layer; a second magnetic layer formed along a surface of said write gap layer remote from said substrate such that the second magnetic layer extends from a portion in which said insulating layer is not embedded to a portion in which said first insulating layer is embedded; a second insulating layer formed on said write gap layer to have a coplanar surface with a surface of said second magnetic layer opposite to said write gap layer; a thin film coil, at least a part of which is formed on said coplanar surface of said second insulating layer such that the thin film coil is formed in an electrically isolated and separated manner; and a third magnetic layer coupled with a portion of a surface of said second magnetic layer opposite to said write gap layer such that a front end surface of the third magnetic layer is retarded from a front end surface of the second magnetic layer and magnetically coupled with said first magnetic layer at a rear portion remote from an air bearing surface; and an air bearing surface formed on a basis of a throat height zero reference position which is constituted by an edge of said first insulating layer embedded in the recess formed in the first magnetic layer.
2. A thin film magnetic head as claimed in claim 1 , wherein said air bearing surface is formed such that an edge of the insulating layer embedded in the recess formed in the first magnetic layer is used as a throat height zero reference position.
3. The thin film magnetic head according to claim 2 , wherein a rear edge of a narrow width portion of said second magnetic layer is retarded beyond the throat height zero reference position.
4. The thin film magnetic head as claimed in claim 1 , wherein said recess has a tapered side wall.
5. The thin film magnetic head as claimed in claim 4 , wherein a taper angle of said tapered side wall of the recess is set to about 15-90 degrees.
6. The thin film magnetic head as claimed in claim 1 , wherein said second magnetic layer is made of a magnetic material having a higher saturation magnetic flux density than said third magnetic layer.
7. The thin film magnetic head as claimed in claim 6 , wherein said magnetic material having a high saturation magnetic flux density and constituting said second magnetic layer is a permalloy NiFe (50%, 50%) or a FeN.
8. The thin film magnetic head as claimed in claim 1 , wherein said second first insulating layer is formed by an inorganic insulating layer.
9. The thin film magnetic head according to claim 8 , wherein said inorganic insulating layer is made of alumina, silicon oxide or silicon nitride.
10. The thin film magnetic head as claimed in claim 1 , wherein said second insulating layer is formed by an inorganic insulating layer, and a first layer thin film coil of said thin film coil is supported by said inorganic insulating layer in an insulating and isolating manner.
11. The thin film magnetic head according to claim 10 , wherein a second layer thin film coil of said thin film coil is arranged on a surface of said inorganic insulating layer remote from the substrate and is supported by a photoresist insulating layer in an insulated and isolated manner.
12. The thin film magnetic head according to claim 1 , wherein said second magnetic layer includes a narrow width portion constituting a pole portion and a wide width portion connected with said third magnetic layer.
13. The thin film magnetic head according to claim 1 , wherein said recess has a depth of about 0.5-2.0 m.
14. The thin film magnetic head according to claim 1 , wherein said thin film magnetic head is constructed as a combination type thin film magnetic head including a magnetoresistive type thin film magnetic head arranged between said substrate and said first magnetic layer.
15. The thin film magnetic head according to claim 14 , wherein one of magnetic shields for said magnetoresistive type thin film magnetic head is constituted by said first magnetic layer.
Cooperative Patent Classification codes for this invention. Click any code to explore related patents in that topic.
March 31, 1999
May 14, 2002
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